DCDOC
We have a 2005 FSC2800 WW. It is just over 30’ from hitch to backdoor. We’ve towed it over 25,000 miles and travelled all over the country and never had a problem.
We use the same type of WD hitch and sway bar. Proper loading is the biggest factor in the trailer handling that we’ve found. I have repositioned my load when I noticed a problem. This is a very rare event and normally means we slide our two Lazy Boys or move some other packed boxes or suitcases forward.
While I have no 5th wheel experience I wouldn’t be concerned about the bumper tow.
Hap